A polymer PTC element comprising a polymer PTC component which contains conductive fillers and a polymer material, and a metal electrode placed on at least one surface of the polymer PTC component is used in various electrical devices. For example, such a PTC element is used as a circuit protection device in a circuit which is used when charging a secondary battery of a cellphone.
When incorporating such polymer PTC element in an electrical device, a PTC element having a lead connected onto the metal electrode, which is supplied as a PTC device, is connected by soldering to an electrical component (for example, wiring, electrode of an electrical part, or a lead which forms a protection circuit), thereby incorporating the PTC device in the prescribed circuit to provide a prescribed function in an electrical device. (See Japanese Patent Laid-open Publication No. 2003-77705.